This article traces the history of Inquiry into the Marriage Amendment Bill 2004 and ensuing legislation and explores constitutional and international law issues in the context of that history. The authors argue that the aborted Inquiry and the Marriage Amendment Bill 2004 significantly weaken Australia's claim to be an egalitarian society and serve as a poignant reminder that pseudoegalitarian ideals such as 'mateship' and a 'fair go' are no protection against measures that marginalise vulnerable minorities for political gain. The resultant amendments to the Marriage Act 1961 perpetuate homophobia and marginalise gay, lesbian, transgender and intersex Australians.